Interior equipements of aircraft include numerous electrical devices that have to be fixed into place, some of which devices are provided as prefabricated units. The installation effort essentially arises from the necessary connection to electrical supply lines and from attachment of the device at the intended installation location.
The so-called exit signs, small lamp assemblies comprising lighting means, which signs serve as marker lights for cabin exits and for escape routes, and which in the case of the aircraft sustaining damage also act as emergency lighting, are one group of such electrical devices.
Exit signs are part of the safety-relevant assemblies in an aircraft. They are checked daily as part of pre-start checks. If any deficiencies or malfunctions are detected, the operational readiness of such assemblies must be restored completely before the aircraft is allowed to take off.
Normally, when the cabin is fitted out, various electrical devices, in particular exit signs, are connected to electrical supply lines that have already been installed earlier. In order to have the installation freedom necessary for this, the lines have to have a certain overlength if they have been installed in hollow spaces which are difficult to access.
Following a different practice in the installation of electrical devices, at present first the device is mechanically installed, and thereafter the electrical connections are established by way of individual plug-type contacts.
Both the above approaches are associated with a number of disadvantages. The phase of cabin fitout requires considerable installation effort because the devices have to be attached at the intended installation location, for example by means of screw connections, and by the allocation and connection of numerous (mostly one-pole) plug-type connections for electrically connecting the devices.
As a result of the overlength of the supply lines, which overlength is required for connecting the complete devices, after installation a superfluous line part remains in the region where the supply lines have been installed. This superfluous line part carries the danger of uncontrolled movement and uncertain line routing of the supply lines, as a result of which the danger of chafing arises. In order to prevent damaging the insulation of the cables, expensive chafing protection is thus required, and/or options must be found for attaching the relatively loosely placed cables again after completion of device installation.
Maintenance measures require considerable installation effort because even in the case of exchanging individual components, deinstallation and renewed connection of the device may become necessary. In the context of renewed separation and connection of the individual plug-type connections, any maintenance measure entails a danger of mixing up the connectors, which requires additional troubleshooting and remedial action.
Conventional installation requires the use of various tools and a multitude of loose components, for example screws and various shim components. These have to be kept in stock at the location where maintenance may become necessary. Especially in the case of exit signs this is an additional disadvantage in that exchange of these safety-relevant components must be able to be carried out practically anywhere.
Adapting the electrical devices to be installed to the requirements of the place of installation can result in a considerable increase in the weight of the devices when installation is to take place by integration in other assemblies and when such integration requires adaptive constructive measures. Extensive integration also increases production costs.
There may be a need for an attachment system for an electrical device, which provides easy installation of electrical devices in the cabin region of aircraft.